Needle jogging mechanisms



Nov. 4', 1969 w. o. SZUBA ETAL 3,476,066

NEEDLE JOGGING MECHANISMS Filed June 16, 196'? 5 Sheets-Sheet 1 WaIfer'D. .Szuba and James H. Human Jr:

WITNESS BY fi w W g FIG.

INVENTORS.

Nov. 4, 1969 w, szu ETAL 3,476,066

NEEDLE JOGGING MECHANISMS Filed June 16. 1967 5 Sheets-Sheet 2 I INVENTORS. Walter D. Szuba and James H. Hannen Jr,

- BY mmzss fiavz 41mm Nov. 4, 1969 w. D. SZUBA L 3,476,066

NEEDLE JOGGING MECHANISMS Filed June 16, 1967 5 SheeE -Sheet 5 wvsuronrs Walter D. Szuba and JCImeS H. Human Jr:

NOV. 4, 1969 w, 13, szu ET AL 3,476,066

NEEDLE JOGGING MECHANISMS Filed June 16, 1957 5 Sheets-Sheet 4- Fig. 6

INVENTORS. Waller D. Szuba and James H. Human Jr:

) wmvsss Nov. 4, 1969 w. sz ET AL NEEDLE JOGGING MECHANISMS 5 Sheets-Sheet 5 Filed June 16, 1967 INVENTORS. Walter D. Szuba and Jdmes H. Human J1 AUURNiY WITNESS United States Patent U.S. Cl. 112-158 7 Claims ABSTRACT OF THE DISCLOSURE The position of a wedge between two cam followers, one of which contacts a pattern cam, is changed to change the stitch width. The other cam follower is biased against the wedge by a leaver which is shiftably connected to a connecting rod between a needle bar gate and means for imparting lateral oscillation to the needle bar gate.

Background of the invention Field of the invention.The invention relates to vibrating needle zigzag stitch forming mechanisms.

Description of the prior art.-Heretofore, there have been two types of zigzag mechanisms, one in which lateral oscillation is imparted to a needle bar directly by a pattern cam and the other in which lateral oscillation is imparted to the needle bar by a constant breadth cam with the needle jogging motion modified by a pattern cam. In the second type of needle jogging mechanism, there has been a paucity of versatile as well as practical mechanisms for changing the amplitude of lateral oscillation of the needle bar.

Summary of the invention It is therefore an object of the invention to provide an improved needle jogging mechanism for a sewing machine.

Another object of the invention is to provide a needle jogging mechanism in which the majority of the parts are mounted on a single cam shaft.

Another object of the invention is to provide a needle jogging mechanism having a manual lever and removable parts which can be selectively provided for changing the amplitude of lateral oscillation of a needle bar.

Other objects and a fuller understanding of the invention may be had by referring to the description and claims taken in conjunction with the accompanying drawmgs.

Brief description of the drawings FIG. 1 is a vertical longitudinal cross sectional View of a sewing machine incorporating a first modification of the invention,

FIG. 2 is a top plan view partly in section of the sewing machine of FIG. 1 with the top cover removed,

FIG. 3 is a cross sectional view taken substantially along the line 3-3 in FIG. 2.

FIG. 4 is a cross sectional view taken substantially along the line 44 in FIG. 2.

FIG. 5 is a partially exploded perspective view of the needle jogging mechanism of the sewing machine of FIG. 1,

FIG. 6 is a bottom plan view of the sewing machine,

FIG. 7 is a top plan view partly in section of a sewing machine incorporating a second modification of the invention,

FIG. 8 is a cross sectional view taken substantially along the line 88 in FIG. 7, and

FIG. 9 is a cross sectional view taken substantially along the line 9-9 in FIG. 7.

3,476,066 Patented Nov. 4, 1969 'ice Description of the preferred embodiments With reference to FIGS. 1 to 6 of the drawings, a first modification of the invention is shown embodied in a sewing machine having a frame including a work supporting bed 21, a hdllow standard 22 rising from one end of the bed, a hollow bracket arm 23 at the top of the standard overhanging the bed and a sewing head 24 at the free end of the bracket arm.

Mounted in the sewing head is a needle bar mechanism indicated generally at 25. A compensating shuttle mechanism indicated generally at 26 is mounted in the bed, and a needle jogging mechanism indicated generally at 27 is mounted in the bracket arm.

The needle bar mechanism includes a needle bar gate 28. The needle bar gate has two lugs 29 and 30 extending from the front side and two lugs 31 and 32 extending from the rear side. The front lugs have coaxial bores 33 and 34 and the rear lugs have somewhat larger coaxial bores 35 and 36. The needle bar gate is pivotally mount d on a hinge pin 37 which extends through the bores in the front lugs. The hinge pin is vertically held in a bore 38 in a lower boss 39 in the sewing head by a setscrew 40 and also in a bore 41 in an upper boss 42 by a setscrew 43. A collar 44 connected to the hinge pin by a setscrew 45 sandwiches the lower front lug on the needle bar gate between the collar and the lower boss in the sewing head.

Slidably mounted in the bores in the rear lugs on the needle bar gate is a needle bar 46. A needle 47 is connected to the lower end of the needle bar by a clamping screw 48 on a needle clamp 49. Endwise reciprocating motion is imparted to the needle bar by a crank 50 on the end of a horizontal arm shaft 51 longitudinally journaled in a bearing 52 and a bore 53 in the bracket arm. Rotating motion is imparted to the arm shaft through a handwheel 54 and pulley 55 on the standard end of the arm shaft. The crank 50 is connected to the needle bar by a link 56 which is pivotally mounted on a crankpin 57 on the crank and a laterally extending pin 58 on a clamp 59 which is connected to the needle bar by a setscrew 60.

The compensating shuttle mechanism 26 including an oscillating shuttle 61 in a shuttle housing 62 on the end of a bed shaft 63 which is journaled in a bearing 64 and a bore 65 in the bed. Oscillating motion is imparted to the bed shaft by a vertical pitman 66 in the standard. The pitman has a fork 67 which embraces an eccentric 68 on the arm shaft. The lower end of the pitman is pivotally connected to a first rock arm 69 on a short rock shaft 70 by a pivot screw 71. The rock shaft is held between two pivot pins 72 in the bed. A second rock arm 73 on the rock shaft is pivotally connected to a crank 74 on the bed shaft to transmit oscillating motion to the bed shaft.

Motion to compensate for lateral oscillation of the needle is imparted to the shuttle by a horizontal connecting rod 75 in the bracket arm. One end of the connecting rod is pivotally connected to the top of the needle bar gate 28 by a pivot pin 76. The other end of the connecting rod is pivotally connected to a rock arm 77 on a vertical rock shaft 78 in the standard by a pivot pin 79. The rock shaft is journaled in bores 80 and 81 in two bosses 82 and 83 in the standard. A slide block 84 on a rock arm 85 on the lower end of the rock shaft extends between two flanges 86 and 87 on the bed shaft to trans- Init endwise reciprocating motion to the bed shaft and hence compensating motion to the shuttle. A slide pin 88 held in a horizontal bore 89 in a front leg 90 of the sewing machine by a setscrew 91 permits compensating motion of the shuttle housing while preventing rotation.

The needle jogging mechanism 27 includes a cam shaft 92. The cam shaft has an eccentric stud 93 which is held in a vertical bore 94 in the bracket arm by a setscrew 95. Iournaled on the cam shaft is an integral threepiece part 96 including a constant breadth cam 97 sandwiched between a lower worm wheel 98 and an upper eccentric 99. The worm wheel meshes with a worm 100 on the arm shaft. The eccentric stud 93 of the cam shaft enables the worm wheel to be adjusted relative to the worm. The worm wheel has twice the number of teeth as the worm thus providing a two-to-one speed reduction with the worm wheel rotating once for every two rotations of the arm shaft.

Mounted in the bracket arm is a horizontal pitman 101 having three forks 102, 103 and 104. The middle fork 103 embraces the constant breadth cam 97 on the integral three-piece part. The fork 104 nearest the standard embraces a stud 105 beneath a flange 106 on the stud. The stud is held in a tapped hole 107 in a boss 108 in the bracket arm by a setscrew which is not shown. The remaining fork 102 of the pitman embraces a head 109 of a pivot screw 110 in a tapped hole 111 in a boss 112 in the bracket arm.

A needle position control subassembly indicated generally at 113 is also mounted in the "bracket arm. The needle position control subassembly includes a lever 114, a bracket 115, a handle 116, and a stud 117. The lever has a bore 118 by which it is pivotally mounted on a shoulder 119 of the pivot screw 110 which is embraced by one of the forks of the three-fork pitman. The bracket 115 is connected to the free end of the lever by the stud 117, and the handle is connected to the free end of the bracket by a screw 120. A stud 121 on the handle seats in a small hole 122 in the bracket to prevent pivotal movement of the handle relative to the bracket. The handle of the needle position control subassembly extends through a first horizontal slot 123 in a control panel 124 on the front of the bracket arm.

Pivotally mounted on a shoulder 125 of a pivot screw 126 in a tapped hole 127 in the lever 114 of the needle position control subassembly is a rock arm 128 having an upper arcuate slideway 129 and a lower slideway 130. The lower slideway mates with a slide block 131 pivotally mounted on the three-fork pitman 101 by a pivot pin 132 to receive oscillating motion from the constant breadth cam 97. The upper arcuate slideway also houses a slide block 133 which is arcuate to conform to the contour of the arcuate slideway. The arcuate slide block has an eccentric pivot screw 134 with a head 135 which slides in a widened portion 136 at the bottom of the arcuate slideway. The widened portion of the arcuate slideway holds the pivot screw in the slideway, and an eccentric 137 connected to the end of the stud 117 on the needle position control subassembly by a screw 138 acts as a stop for the arcuate slide block. The eccentric 137 provides an adjustment feature. A washer 139 is mounted on an eccentric threaded portion of the eccentric pivot screw 134 above the arcuate block, and a connecting rod 140 is pivotally connected to the eccentric pivot screw. The connecting rod is held on the eccentric pivot screw by a nut 141 which is threaded on the eccentric pivot screw. The other end of the connecting rod 140 is pivotally connected to the needle bar gate 28 by a pivot pin 142 to transmit lateral oscillation to the needle bar gate derived from the constant breadth cam 97 on the cam shaft. The pivot pin is held in a bore 143 in the needle bar gate by a setscrew 144.

Returning to the cam shaft, a reduction gear indicated generally at 145 is mounted on the cam shaft. The reduction gear includes a pinion 146 having a hole 147 which mates with the eccentric 99 on the integral three-piece part, and an internal gear 148 which mates with the pinion. The pinion has a radially extending arm 149 with a slot 150 which embraces an eccentric portion 151 above the flange 106 of the stud 105. The eccentric portion of the stud provides an adjustment feature. The internal gear 148 is held on the cam shaft by a screw 152 threaded into a tapped hole 153 in the top of the cam shaft. The eccentric 99 on the integral three-piece part rotates the pinion 146 as guided by the arm 149 around the internal gear 148 to provide a nine-to-one speed reduction. The nine-to-one speed reduction added to the two-to-one speed reduction provided by the worm and worm wheel 98 provides a total eighteen-to-one speed reduction.

Pivotally mounted on the internal gear 148 is a stitchwidth control subassembly indicated generally at 154. The stitch-width control subassembly includes a ring-shaped bracket 155, a smaller bracket 156, a handle 157, and an arcuate wedge 158. The ring-shaped bracket has a hole 159 which mates with a reduced portion 160 of the internal gear 148 to mount the stitch-width control subassembly on the internal gear. The ring-shaped bracket rests on a shoulder 161 formed by the reduced portion of the internal gear. The smaller bracket 156 is connected to the ringshaped bracket by two screws 162, and the handle is connected to the smaller bracket by a screw 163. The handle of-the stitch-width control subassembly extends through a second horizontal slot 164 in the control panel on the front of the bracket arm.

A support ledge 165 extends from the periphery of the ring-shaped bracket. Pivotally mounted on the support ledge by a pivot screw 166 is the arcuate wedge 158 which which has inner and outer curved surfaces 167 and 168, respectively. The inner curved surface of the arcuate wedge bears against a first cam follower pin 169 on a first lever 170. The first lever is pivotally mounted on a shoulder 171 of a spacer 172 on a pivot pin 173. The pivot pin is seated in a bore 174 in a boss 175 in the bracket arm. Bearing against the outer curved surface 168 of the arcuate wedge is a second cam follower pin 176 on a second lever 177 pivotally mounted on a pivot pin 178 also seated in a bore 179 in a boss 180 in the bracket arm. The other end of the second lever is journaled on a shoulder of an eccentric pivot screw 181, and a link 182 is held on an eccentric threaded portion by a nut. The shoulder, eccentric threaded portion, and nut are not shown. The link in turn is pivotally connected by a pivot screw 183 to an intermediate portion of the connecting rod 140 between the needle bar gate and the rock arm 128 having the arcuate slideway thus providing a shiftable connection between the second lever and the connecting rod. The second cam follower pin 176 is biased against the outer curved surface 168 of the arcuate wedge by a torsion spring 184 mounted on a spacer 185 on the pivot pin 178 which connects the second lever to the bracket arm. The torsion spring has two links 186 and 187 with a hook 188 formed at the end of the shorter link by bending the shorter link downwardly 90 degrees, and a hook 189 formed at the end of the longer link by bending the longer link upwardly 90 degrees and then forwardly 90 degrees. The hook on the shorter link bears against the side of the boss 180 in the bracket arm on which the second lever is pivotally mounted, and the hook on the longer link is hooked over the rear side of the second lever at an intermediate portion of the second lever.

Mounted on a hub 190 on the top of the internal gear 148 is a pattern cam 191 having a hole 192 in the center for the hub. The pattern cam rests on a shoulder 193 formed by the hub and the reduced portion of the internal gear. A radial notch 194 is formed off the circumference of the hole in the pattern cam and a radial groove 195 is formed off the circumference of the hole in the reverse side of the pattern cam diametrically opposite from the radial notch. Two screws 196 and 197 on the shoulder formed by the hub and the reduced portion of the pattern cam seat in the radial notch and the radial groove formed in the pattern cam to prevent rotation of the pattern cam relative to the internal gear. A thumb nut 198 is screwed onto threads 199 on the hub to retain the pattern cam on the internal gear. The first cam follower pin 169 contacts the periphery of the pattern cam. Although a pattern cam is shown having a round periphery which does not alter the zigzag motion imparted by the constant breadth cam 97, the pattern cam is freely interchangeable with other pattern cams which can modify the zigzag motion imparted by the constant breadth cam to produce an unlimited variety of stitch patterns.

With specific reference to FIG. 5, if it is desired to provide a needle jogging mechanism without a pattern cam, all of the parts enclosed by the dashed lines are freely removable and a manual stitch-width control subassembly indicated generally at 200 can be provided. Conversely, if a manual stitch-width control subassembly is provided, a sewing machine can easily be converted to pattern cam operation by removing the manual stitchwidth control subassembly and adding the parts enclosed by the dashed lines. The manual stitch-width control subassembly includes a lever or bell crank 201 having two arms 202 and 203, an extension 204, and a handle 205. The bell crank has a bore 206 in the elbow formed by the two arms and a bore 207 at the end of one of the arms 203. The bell crank is pivotally mounted in the bracket arm by a pivot screw 208 having a shoulder 209 for the bore in the elbow of the bell crank. The bell crank is pivotally connected to the link 181 in place of the second lever 177 by the pivot screw 182 which connected the second lever to the link. The pivot screw extends into the bore 207 at the end of the arm 203 of the bell crank. Connected to the other arm of the bell crank by a screw 210 is the extension 204, and connected to the extension is the handle of the manual stitch-width control subassembly. A stud 211 on the arm of the bell crank seats in a small bore 212 in the extension to prevent pivotal movement of the extension relative to the arm of the bell crank. The handle of the stitch-width control subassembly extends through a third horizontal slot in the control panel on the front of the bracket arm. The third horizontal slot is not shown.

In order of assembly, the major removable parts are: the pinion 146; the internal gear 148; the screw 152 which holds the internal gear on the cam shaft; the stitchwidth control subassembly 154 including the ring-shaped bracket, the smaller bracket 156, the handle, and the arcuate wedge; the pattern cam 191; the thumb nut 198 which holds the pattern cam on the internal gear; the first lever 170 with the first cam follower pin; the second lever 177 with the second cam follower pin; and the torsion spring 184 which biases the second cam follower pin against the outer curved surface of the arcuate wedge.

With reference to FIGS. 7 to 9, a second modification of the invention is shown embodied in a sewing machine which can be similar to the first modification. In addition, many of the parts of the second modification are substantially the same as those in the first modification. Therefore, the second modification will be described only insofar as it differs from the first modification. Generally, substantially like parts are identified by like reference numerals but suffixed with a letter a in the second modification.

In the second modification, two cam shafts 213 and 214 are provided. One of the cam shafts has a pilot portion 215 which seats in a bore 216 in a boss 217 in the bracket arm and is held in the bore by a setscrew 218. A worm wheel 219 is mounted on an eccentric portion 220 of the cam shaft. The worm wheel mates with a worm 221 on the arm shaft. The worm wheel has twice the number of teeth as the worm thus providing a twoto-one speed reduction with the worm wheel rotating once for every two rotations of the arm shaft. The eccentric portion 220 of the cam shaft enables the worm wheel to be adjusted relative to the worm.

Mounted on the worm wheel is a constant breadth cam 222 having a stud 223 which seats in a bore 224 in the worm wheel. A setscrew 225 connects the constant breadth cam to the worm wheel. Pivotally mounted on the stud of the constant breadth cam between the worm wheel and a flange 226 underneath the constant breadth cam is a needle position control subassembly indicated generally at 227. The needle position control subassembly includes a lever 228 and a handle 229. A rock arm 230 is pivotally connected to an intermediate portion of the lever of the needle position control subassembly by a pivot screw 231 having a shoulder 232 which mates with a bore 233 in the rock arm. The rock arm has a fork 234 on the bottom which embraces the constant breadth cam, and an arcuate slideway 235 in the top which mates with an arcuate slide block 236. A connecting rod 237 is pivotally connected to the arcuate slide block by a pivot pin 238 and to the needle bar gate by a pivot screw 239 to transmit lateral oscillation derived from the constant breadth cam 222 to the needle bar gate. The handle is connected to the free end of the lever of the stitch-width control subassembly by a screw 240. A stud 241 on the handle seats in a small bore 242 in the lever to prevent pivotal movement of the handle relative to the lever. The handle of the stitch-width control subassembly extends through a first horizontal slot 243 in a control panel 244 on the front of a bracket arm.

The other cam shaft 214 has three portions 245, 246, and 247. The middle portion 246 is larged in diameter than the bottom portion 245 and the upper portion 247 is larger in diameter than the middle portion. A smaller flange 248 and a larger flange 249 are formed between the middle and upper portions, and the upper portion has threads 250. The middle portion of the cam shaft is mounted in a bearing 251. The bearing is mounted in a hole 252 in a horizontal platform 253 in the bracket arm. A worm wheel 254 is connected to the bottom portion of the cam shaft by a setscrew 255. The worm wheel meshes with a worm 256 on the arm shaft. The worm Wheel has eighteen times the number of teeth as the worm, thus providing an eighteen-to-one speed reduction with the worm wheel rotating once for every eighteen rotations of the arm shaft.

The stitch-width control subassembly 154a, the two lever 170a and 177a with the cam follower pins 169a and 176a, respectively, and the torsion spring 184a which biases the second cam follower pin against the outer curved surface of the arcuate wedge 158a are substantially the same as those in the first modification of the invention and will be described only insofar as they differ from the first modification. The stitch-width control subassembly 154'a is mounted on the smaller flange 248 between the middle and upper portions of the cam shaft. The free end of the second lever 177a is shiftably connected to an intermediate portion of the connecting rod 237 between the needle bar gate and the rock arm 230 having the arcuate slideway by a pivot pin 257 which seats in a longitudinal slot 258 in the connecting rod. A pattern cam 259 is mounted on the upper portion of the cam shaft and rests on the larger flange 249 between the middle and upper portions of the cam shaft. A thumb nut 260 is screwed onto the threads on the upper portion of the cam shaft to retain the pattern cam on the cam shaft. As in the first modification of the invention, many of the parts are freely removable for replacement by a manual stitch-width control subassembly.

In operation, in both modifications of the invention, rotation of the constant breadth cam 97 or 222 to rock the rock arm 128 or 230 imparts lateral oscillation to the needle bar gate 28 or 2811 through the connecting rod or 237 between the needle bar gate and an arcuate slide block 133 or 236 in an arcuate slideway formed in the rock arm. The lateral position of the needle bar gate and hence the lateral position of the needle can be changed by shifting the handle 116 or 229 of the needle position control subassembly to change the angular orientation of the rock arm. In the first modification, the constant breadth cam 97 imparts motion to the three-fork pitman 101 which converts the motion to rectilinear motion to obtain an optimum means for imparting the precise amount of motion to the rock arm 128.

In both modifications, the pattern cam 191 or 259 modifies the needle jogging motion imparted by the constant breadth cam 97 or 222 according to the pattern on the pattern cam through the cam follower pins 169 and 176 or 169a and 176a and the second lever 177 or 177a which is shiftably connected to an intermediate portion of the connecting rod 140 or 237 between the needle bar gate and the rock arm 128 or 230 having the arcuate slideway. In order to change the amplitude of lateral oscillation of the needle bar gate, the handle 157 or 157a of the stitch-width control subassembly is shifted to pivot the ring-shaped bracket 155 or 155a and hence shift the position of the arcuate wedge 158 or 158a between the two cam follower pins 169 and 176 or 169a and 176a.'The resulting change in distance between the two cam follower pins changes the position of the arcuate slide block 133 or 236 in the arcuate slideway in the rock arm. The change in position of the arcuate slide block changes the distance of the arcuate slide block from the pivot screw 126 or 231 for the rock arm thus changing-the amplitude of lateral oscillation transmitted to the needle bar gate. When the thinnest portion of the arcuate wedge is between the two cam follower pins, the amplitude of lateral oscillation of the needle bar gate is not changed. Hence, the thinnest portion of the arcuate wedge represents no change in the amplitude of lateral oscillation of the needle bar gate and the widest portion of the arcuat wedge represents the greatest change in the amplitude of lateral oscillation of the needle bar gate.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention.

Having thus set forth the nature of the invention, what is claimed is:

1. A needle jogging mechanism for a sewing machine having a frame, a needle bar gate, means for mounting the needle bar gate in the frame for lateral oscillation, a needle bar for a needle, means for mounting the needle bar on the needle bar gate for endwise reciprocation, and means for imparting endwise reciprocation to the needle bar, said needle jogging mechanism comprising means for imparting lateral oscillation to the needle bar gate, a connecting rod between the needle bar gate and the means for imparting lateral oscillation to the needle bar gate, a cam shaft mounted in the frame, a pattern cam carried on said cam shaft, means for rotating the pattern cam, an arcuate wedge having opposed first and second surfaces which form the wedge, means for shiftably mounting the wedge in the frame, including a bracket pivotally mounted on the cam shaft, 9. support ledge on the periphery of the bracket, and means for pivotally mounting the wedge on the support ledge, a first lever, a first cam follower on the first lever, means for pivotally mounting the first lever in the frame with the cam follower between the first surface of the wedge and the periphery of a pattern cam on the cam shaft, a second lever, a second cam follower on the second lever, means for mounting the second lever in the frame with the second cam follower in contact with the second surface of the wedge, means for shiftably conmeeting the free end of the second lever to an intermediate portion of the connecting rod between the needle bar gate and the means for imparting lateral oscillation to the needle bar gate, biasing means for biasing the second lever so that the second cam follower is biased against the second surface of the Wedge, and means for pivoting said bracket relative to the cam shaft for shifting the wedge so that different portions of the opposed first and second surfaces of the wedge can be presented to the cam followers to change the amplitude of lateral oscillation of the needle bar gate.

2. The needle jogging mechanism of claim 1 which includes a reduction gear on the cam shaft to reduce the speed of a pattern cam on the cam shaft relative to the means for rotating the pattern cam.

3. The needle jogging mechanism of claim 2 in which the reduction gear includes an eccentric mounted on the cam shaft, a pinion having teeth and mounted on the eccentric, an arm extending from the pinion, means for shiftably and pivotally connecting the arm to the frame of the sewing machine, an internal gear having teeth and mounted on the cam shaft with the teeth meshing with the teeth of the pinion, and means for mounting the pattern cam to rotate with the internal gear.

4. The needle jogging mechanism of claim 1 in which the means for imparting lateral oscillation to the needle bar gate includes a second cam shaft rotatably mounted in the frame, a cam connected to the second cam shaft, means for rotating the cam, a rock arm having a slideway and a fork pivotally mounted in the frame with the fork embracing the cam on the second cam shaft, and a slide block in the slideway pivotally connected to the connecting rod from the needle bar gate.

5. The needle jogging mechanism of claim 1 in which the means for imparting lateral oscillation to the needle bar gate includes a rock arm having a slideway and pivotally mounted in the frame, a slide block in the slideway pivotally connected to the connecting rod from the needle bar gate, a cam connected to the cam shaft, and a pitman pivotally connected to the free end of the rock arm and having a fork embracing the cam.

6. The needle jogging mechanism of claim 5 which includes means for shifting the rock arm to change the lateral position of the needle bar.

7. The needle jogging mechanism of claim 1 which includes a manual lever, means for removably and pivotally mounting the manual lever in the frame, and means for removably and pivotally connecting the manual lever to the connecting rod between the needle bar gate and the means for imparting lateral oscillation to the needle bar gate; in which said pattern cam on the cam shaft, said means for shiftably mounting the wedge in the frame, said first and second levers, and said biasing means for biasing the second lever are removable parts; and in which the manual lever and the foregoing removable parts can selectively be provided for changing the amplitude of lateral oscillation of the needle bar gate.

References Cited UNITED STATES PATENTS 3,053,207 9/1962 Adler 112-158 3,105,449 10/1963 Szostal et al. 112-158 3,369,510 2/1968 Taketomi 112158 RICHARD J. SCANLAN, 111., Primary Examiner 

